Physical Characterization of Rocks in Thung Nui Hot Spring, Satun Province, the South of Thailand

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In this study, Physical properties of rocks from geothermal reservoir were investigated. To describe rock properties of the selected outcrops, density, radioactivity, and heat production were researched. The obtained density of granite rock from Triassic period and limestone rock from Ordovician period were 2,648±112 kg/m3 and 2,637±96 kg/m3, respectively. Radioactivity of 226Ra 232Th and 40K of granite rock were measured as 109.9±17.2 Bq/kg, 134.2±9.5 Bq/kg, and 1,569.3±75.7 Bq/kg, respectively. For limestone rock, it shows 13.8±6.4 Bq/kg, 23.3±7.7 Bq/kg, and 394.1±117.8 Bq/kg, respectively. After grinding the samples, radioactivity values of 226Ra, 232Th, and 40K were measured by gamma spectrometer. It was found that the concentration of 238U, 232Th, and 40K in granite rocks from Triassic period were 8.90 ppm, 33.07 ppm, and 5.06%, and limestone rocks from Ordovician period are 1.11 ppm, 5.73 ppm, and 1.27%, respectively. The physical properties of reservoir rocks giving geological parameter information were necessary to understand geothermal system of the area in this study and to develop renewable energy for the community.

Abstract: Constant geothermal temperature is necessary to the long-term efficient operation of the ground source heat pump. SGSHP (Solar-Ground Source Heat Pump) system adopts solar energy as assistant heat source to maintain the geothermal temperature in cold regions. A design method based on equilibrium geothermal temperature was illustrated with an example of a villa in Beijing, China. Flowchart and control strategy of the combined system were introduced. Average heat collection efficiency and necessary area of the solar collector were derived on the basis of energy balance equation. Geothermal temperature variation was also researched to test if the solar energy and geothermal energy were reasonably matched. Results show that the combined system can maintain a constant geothermal temperature if it is well designed. The solar-ground source heat pump system is efficient, reliable and energy-saving.

Abstract: Yanshan orogenic belt and its nearby area have thinner earth crust structure, so the asthenosphere of earth mantle upwells and directly bake earthcrust, resulting in Yanshan geothermal anomaly. The type and distribution of thermal spring are controlled by an EW major fault. Thermal springs can be divided into the outcropping type and the hidden type. The outcropping thermal springs mainly spread over orogenic belt in mountain area distributed over northern of Shangyi- Chicheng-Gubeikou-Chengde-Pingyuan fault belt, Hebei. Average temperature of outcropping thermal springs higher than 60°C. Yanshan’s particular earth dynamics and tectonic structure background makes the thermal springs in this area have great prospects for exploitation and utilization

Abstract: As human overexploitation of non-renewable fossil fuels such as mining resources, the global environment has been severely polluted and damaged, which also poses a threat to human's health. So it is full of demands for renewable and clean energy sources. At present R & D of new energy is also increasing emphasised around the world. HDR as a renewable clean geothermal resources, with large reserves, widely distributed, heat, environmentally friendly development, through the heat exchange technology for power generation, which has a strong potential value.To actively develop new energy and promote the application of HDR power generation technology,we start from the basic characteristics of the HDR, and explore the basic principles of HDR power generation, the key technologies and the development of economic conditions. Meanwhile combined with the geographical characteristics of the environment in China, from the perspective of integration of subject resources,finally we constructively put forward a three-stage strategy for HDR power generation development plan.

Abstract: Beijing-Tianjin-Tangshan- Qinhuangdao area structurally lies in the fault-fold belt before Yanshan orogenic belt. The geothermal springs are divided into two types: the natural outcrop type and the hidden artificial type of heat reservoir, the former of which is controlled by piedmont faulted , extending EW; while the latter of which is controlled by regional structure and geothermal field. Geothermal spring water is low salinity and neutral even low alkaline water, whose chemical type is mainly SO4•HCO3- Na and SO4•Cl•HCO3- Na. As the water is rich in fluoride and multiple heavy metals, it pollutes drinking water, soil, crops in different degree during the development and utilization. H2S and CO2 in the geothermal water also does harm to the atmosphere more or less.